org.lmdbjava.DbiFlags Maven / Gradle / Ivy
/*-
* #%L
* LmdbJava
* %%
* Copyright (C) 2016 - 2023 The LmdbJava Open Source Project
* %%
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* #L%
*/
package org.lmdbjava;
/**
* Flags for use when opening a {@link Dbi}.
*/
public enum DbiFlags implements MaskedFlag {
/**
* Use reverse string keys.
*
*
* Keys are strings to be compared in reverse order, from the end of the
* strings to the beginning. By default, keys are treated as strings and
* compared from beginning to end.
*/
MDB_REVERSEKEY(0x02),
/**
* Use sorted duplicates.
*
*
* Duplicate keys may be used in the database. Or, from another perspective,
* keys may have multiple data items, stored in sorted order. By default keys
* must be unique and may have only a single data item.
*/
MDB_DUPSORT(0x04),
/**
* Numeric keys in native byte order: either unsigned int or size_t. The keys
* must all be of the same size.
*/
MDB_INTEGERKEY(0x08),
/**
* With {@link #MDB_DUPSORT}, sorted dup items have fixed size.
*
*
* This flag may only be used in combination with {@link #MDB_DUPSORT}. This
* option tells the library that the data items for this database are all the
* same size, which allows further optimizations in storage and retrieval.
* When all data items are the same size, the {@link SeekOp#MDB_GET_MULTIPLE}
* and {@link SeekOp#MDB_NEXT_MULTIPLE} cursor operations may be used to
* retrieve multiple items at once.
*/
MDB_DUPFIXED(0x10),
/**
* With {@link #MDB_DUPSORT}, dups are {@link #MDB_INTEGERKEY}-style integers.
*
*
* This option specifies that duplicate data items are binary integers,
* similar to {@link #MDB_INTEGERKEY} keys.
*/
MDB_INTEGERDUP(0x20),
/**
* With {@link #MDB_DUPSORT}, use reverse string dups.
*
*
* This option specifies that duplicate data items should be compared as
* strings in reverse order.
*/
MDB_REVERSEDUP(0x40),
/**
* Create the named database if it doesn't exist.
*
*
* This option is not allowed in a read-only transaction or a read-only
* environment.
*/
MDB_CREATE(0x4_0000);
private final int mask;
DbiFlags(final int mask) {
this.mask = mask;
}
@Override
public int getMask() {
return mask;
}
}